Joanne D. Schuijf

Diagnostic accuracy of 64-slice computed tomography coronary angiography: a prospective, multicenter, multivendor study.

OBJECTIVES This study sought to determine the diagnostic accuracy of 64-slice computed tomographic coronary angiography (CTCA) to detect or rule out significant coronary artery disease (CAD). BACKGROUND CTCA is emerging as a noninvasive technique to detect coronary atherosclerosis. METHODS We conducted a prospective, multicenter, multivendor study involving 360 symptomatic patients with acute and stable anginal syndromes who were between 50 and 70 years of age and were referred for diagnostic conventional coronary angiography (CCA) from September 2004 through June 2006. All patients underwent a nonenhanced calcium scan and a CTCA, which was compared with CCA. No patients or segments were excluded because of impaired image quality attributable to either coronary motion or calcifications. Patient-, vessel-, and segment-based sensitivities and specificities were calculated to detect or rule out significant CAD, defined as >or=50% lumen diameter reduction. RESULTS The prevalence among patients of having at least 1 significant stenosis was 68%. In a patient-based analysis, the sensitivity for detecting patients with significant CAD was 99% (95% confidence interval [CI]: 98% to 100%), specificity was 64% (95% CI: 55% to 73%), positive predictive value was 86% (95% CI: 82% to 90%), and negative predictive value was 97% (95% CI: 94% to 100%). In a segment-based analysis, the sensitivity was 88% (95% CI: 85% to 91%), specificity was 90% (95% CI: 89% to 92%), positive predictive value was 47% (95% CI: 44% to 51%), and negative predictive value was 99% (95% CI: 98% to 99%). CONCLUSIONS Among patients in whom a decision had already been made to obtain CCA, 64-slice CTCA was reliable for ruling out significant CAD in patients with stable and unstable anginal syndromes. A positive 64-slice CTCA scan often overestimates the severity of atherosclerotic obstructions and requires further testing to guide patient management.

Noninvasive Evaluation of the Aortic Root With Multislice Computed Tomography : Implications for Transcatheter Aortic Valve Replacement

OBJECTIVES In the present study, the anatomy of the aortic root was assessed noninvasively with multislice computed tomography (MSCT). BACKGROUND Transcatheter aortic valve replacement has been proposed as an alternative to surgery in high-risk patients with severe aortic stenosis. For this procedure, detailed knowledge of aortic annulus diameters and the relation between the annulus and the coronary arteries is needed. METHODS In 169 patients (111 men, age 54 +/- 11 years), a 64-slice MSCT scan was performed for evaluation of coronary artery disease. Of these, 150 patients had no or mild aortic stenosis, and 19 patients had moderate to severe aortic stenosis. Reconstructed coronal and sagittal views were used for assessment of the aortic annulus diameter in 2 directions. In addition, the distance between the annulus and the ostium of the right and left coronary arteries and the length of the coronary leaflets were assessed. The LV outflow tract and interventricular septum were analyzed on the single oblique sagittal view at end-diastole. RESULTS The diameter of the aortic annulus was 26.3 +/- 2.8 mm on the coronal view, and 23.5 +/- 2.7 mm on the sagittal view. Mean difference between the 2 diameters was 2.9 +/- 1.8 mm, indicating an oval shape of the aortic annulus. Mean distance between the aortic annulus and the ostium of the right coronary artery was 17.2 +/- 3.3 mm, and mean distance between the annulus and the ostium of the left coronary artery was 14.4 +/- 2.9 mm. In 82 patients (49%), the length of the left coronary leaflet exceeded the distance between the annulus and the ostium of the left coronary artery. There were no significant differences in the diameter of annulus, diameter of sinus of Valsalva, or the distance between the annulus, left coronary leaflet, and the ostium of the left coronary artery, between the patient with and without severe aortic stenosis. CONCLUSIONS The MSCT can provide detailed information on the shape of the aortic annulus and the relation between the annulus and the ostia of the coronary arteries. Thereby, MSCT may be helpful for avoiding paravalvular leakage and coronary occlusion and may facilitate the selection of candidates for transcatheter aortic valve replacement.

Comparison of Aortic Root Dimensions and Geometries Before and After Transcatheter Aortic Valve Implantation by 2- and 3-Dimensional Transesophageal Echocardiography and Multislice Computed Tomography

Background—3D transesophageal echocardiography (TEE) may provide more accurate aortic annular and left ventricular outflow tract (LVOT) dimensions and geometries compared with 2D TEE. We assessed agreements between 2D and 3D TEE measurements with multislice computed tomography (MSCT) and changes in annular/LVOT areas and geometries after transcatheter aortic valve implantations (TAVI). Methods and Results—Two-dimensional circular (&pgr;×r2), 3D circular, and 3D planimetered annular and LVOT areas by TEE were compared with “gold standard” MSCT planimetered areas before TAVI. Mean MSCT planimetered annular area was 4.65±0.82 cm2 before TAVI. Annular areas were underestimated by 2D TEE circular (3.89±0.74 cm2, P<0.001), 3D TEE circular (4.06±0.79 cm2, P<0.001), and 3D TEE planimetered annular areas (4.22±0.77 cm2, P<0.001). Mean MSCT planimetered LVOT area was 4.61±1.20 cm2 before TAVI. LVOT areas were underestimated by 2D TEE circular (3.41±0.89 cm2, P<0.001), 3D TEE circular (3.89±0.94 cm2, P<0.001), and 3D TEE planimetered LVOT areas (4.31±1.15 cm2, P<0.001). Three-dimensional TEE planimetered annular and LVOT areas had the best agreement with respective MSCT planimetered areas. After TAVI, MSCT planimetered (4.65±0.82 versus 4.20±0.46 cm2, P<0.001) and 3D TEE planimetered (4.22±0.77 versus 3.62±0.43 cm2, P<0.001) annular areas decreased, whereas MSCT planimetered (4.61±1.20 versus 4.84±1.17 cm2, P=0.002) and 3D TEE planimetered (4.31±1.15 versus 4.55±1.21 cm2, P<0.001) LVOT areas increased. Aortic annulus and LVOT became less elliptical after TAVI. Conclusions—Before TAVI, 2D and 3D TEE aortic annular/LVOT circular geometric assumption underestimated the respective MSCT planimetered areas. After TAVI, 3D TEE and MSCT planimetered annular areas decreased as it assumes the internal dimensions of the prosthetic valve. However, planimetered LVOT areas increased due to a more circular geometry.

Prognostic value of multislice computed tomography and gated single-photon emission computed tomography in patients with suspected coronary artery disease.

OBJECTIVES This study was designed to determine whether multislice computed tomography (MSCT) coronary angiography has incremental prognostic value over single-photon emission computed tomography myocardial perfusion imaging (MPI) in patients with suspected coronary artery disease (CAD). BACKGROUND Although MSCT is used for the detection of CAD in addition to MPI, its incremental prognostic value is unclear. METHODS In 541 patients (59% male, age 59 +/- 11 years) referred for further cardiac evaluation, both MSCT and MPI were performed. The following events were recorded: all-cause death, nonfatal infarction, and unstable angina requiring revascularization. RESULTS In the 517 (96%) patients with an interpretable MSCT, significant CAD (MSCT > or =50% stenosis) was detected in 158 (31%) patients, and abnormal perfusion (summed stress score [SSS]: > or =4) was observed in 168 (33%) patients. During follow-up (median 672 days; 25th, 75th percentile: 420, 896), an event occurred in 23 (5.2%) patients. After correction for baseline characteristics in a multivariate model, MSCT emerged as an independent predictor of events with an incremental prognostic value to MPI. The annualized hard event rate (all-cause mortality and nonfatal infarction) in patients with none or mild CAD (MSCT <50% stenosis) was 1.8% versus 4.8% in patients with significant CAD (MSCT > or =50% stenosis). A normal MPI (SSS <4) and abnormal MPI (SSS > or =4) were associated with an annualized hard event rate of 1.1% and 3.8%, respectively. Both MSCT and MPI were synergistic, and combined use resulted in significantly improved prediction (log-rank test p value <0.005). CONCLUSIONS MSCT is an independent predictor of events and provides incremental prognostic value to MPI. Combined anatomical and functional assessment may allow improved risk stratification.

A clinical prediction rule for the diagnosis of coronary artery disease: validation, updating, and extension

AIMS The aim was to validate, update, and extend the Diamond-Forrester model for estimating the probability of obstructive coronary artery disease (CAD) in a contemporary cohort. METHODS AND RESULTS Prospectively collected data from 14 hospitals on patients with chest pain without a history of CAD and referred for conventional coronary angiography (CCA) were used. Primary outcome was obstructive CAD, defined as ≥ 50% stenosis in one or more vessels on CCA. The validity of the Diamond-Forrester model was assessed using calibration plots, calibration-in-the-large, and recalibration in logistic regression. The model was subsequently updated and extended by revising the predictive value of age, sex, and type of chest pain. Diagnostic performance was assessed by calculating the area under the receiver operating characteristic curve (c-statistic) and reclassification was determined. We included 2260 patients, of whom 1319 had obstructive CAD on CCA. Validation demonstrated an overestimation of the CAD probability, especially in women. The updated and extended models demonstrated a c-statistic of 0.79 (95% CI 0.77-0.81) and 0.82 (95% CI 0.80-0.84), respectively. Sixteen per cent of men and 64% of women were correctly reclassified. The predicted probability of obstructive CAD ranged from 10% for 50-year-old females with non-specific chest pain to 91% for 80-year-old males with typical chest pain. Predictions varied across hospitals due to differences in disease prevalence. CONCLUSION Our results suggest that the Diamond-Forrester model overestimates the probability of CAD especially in women. We updated the predictive effects of age, sex, type of chest pain, and hospital setting which improved model performance and we extended it to include patients of 70 years and older.

Transcatheter aortic valve implantation: role of multi-detector row computed tomography to evaluate prosthesis positioning and deployment in relation to valve function

AIMS Aortic regurgitation after transcatheter aortic valve implantation (TAVI) is one of the most frequent complications. However, the underlying mechanisms of this complication remain unclear. The present evaluation studied the anatomic and morphological features of the aortic valve annulus that may predict aortic regurgitation after TAVI. METHODS AND RESULTS In 53 patients with severe aortic stenosis undergoing TAVI, multi-detector row computed tomography (MDCT) assessment of the aortic valve apparatus was performed. For aortic valve annulus sizing, two orthogonal diameters were measured (coronal and sagittal). In addition, the extent of valve calcifications was quantified. At 1-month follow-up after procedure, MDCT was repeated to evaluate and correlate the prosthesis deployment to the presence of aortic regurgitation. Successful procedure was achieved in 48 (91%) patients. At baseline, MDCT demonstrated an ellipsoid shape of the aortic valve annulus with significantly larger coronal diameter when compared with sagittal diameter (25.1 +/- 2.4 vs. 22.9 +/- 2.0 mm, P < 0.001). At follow-up, MDCT showed a non-circular deployment of the prosthesis in six (14%) patients. Moderate post-procedural aortic regurgitation was observed in five (11%) patients. These patients showed significantly larger aortic valve annulus (27.3 +/- 1.6 vs. 24.8 +/- 2.4 mm, P = 0.007) and more calcified native valves (4174 +/- 1604 vs. 2444 +/- 1237 HU, P = 0.005) at baseline and less favourable deployment of the prosthesis after TAVI. CONCLUSION Multi-detector row computed tomography enables an accurate sizing of the aortic valve annulus and constitutes a valuable imaging tool to evaluate prosthesis location and deployment after TAVI. In addition, MDCT helps to understand the underlying mechanisms of post-procedural aortic regurgitation.

Evaluation of plaque characteristics in acute coronary syndromes: non-invasive assessment with multi-slice computed tomography and invasive evaluation with intravascular ultrasound radiofrequency data analysis

AIMS Atherosclerotic plaque characteristics play an important role in the development of coronary events. We investigated coronary plaque characteristics on multi-slice computed tomography (MSCT) and virtual histology intravascular ultrasound (VH IVUS) in patients with acute coronary syndromes (ACS) and stable coronary artery disease (CAD). METHODS AND RESULTS Fifty patients (25 with ACS, 25 with stable CAD) underwent 64-slice MSCT followed by VH IVUS in 48 (96%) patients. In ACS patients, 32% of plaques were non-calcified on MSCT and 59% were mixed [corresponding odds ratio (95% confidence intervals): 3.9 (1.6-9.5), P = 0.003 and 3.4 (1.6-6.9), P = 0.001, respectively]. In patients with stable CAD, completely calcified lesions were more prevalent (61%). On VH IVUS, the percentage of necrotic core was higher in the plaques of ACS patients (11.16 +/- 6.07 vs. 9.08 +/- 4.62% in stable CAD, P = 0.02). In addition, thin cap fibroatheroma was more prevalent in ACS patients (32 vs. 3% in patients with stable CAD, P < 0.001) and was most frequently observed in mixed plaques on MSCT. Plaque composition both on MSCT and VH IVUS was identical between culprit and non-culprit vessels of ACS patients. CONCLUSION On MSCT, differences in plaque characterization were demonstrated between patients with ACS and stable CAD. Plaques of ACS patients showed features of vulnerability to rupture on VH IVUS. Potentially, MSCT may be useful for non-invasive identification of atherosclerotic plaque patterns associated with higher risk.

Noninvasive Evaluation of Coronary Sinus Anatomy and Its Relation to the Mitral Valve Annulus Implications for Percutaneous Mitral Annuloplasty

Background— Percutaneous mitral annuloplasty has been proposed as an alternative to surgical annuloplasty. In this respect, evaluation of the coronary sinus (CS) and its relation with the mitral valve annulus (MVA) and the coronary arteries is relevant. The feasibility of evaluating these issues noninvasively with multislice computed tomography was determined. Methods and Results— In 105 patients (72 men, age 59±11 years), 64-slice multislice computed tomography was performed for noninvasive evaluation of coronary artery disease. Thirty-four patients with heart failure and/or severe mitral regurgitation were included. Three-dimensional reconstructions and standard orthogonal planes were used to assess CS anatomy and its relation with the MVA and circumflex artery. In 71 patients (68%), the circumflex artery coursed between the CS and the MVA with a minimal distance between the CS and the circumflex artery of 1.3±1.0 mm. The CS was located along the left atrial wall, rather than along the MVA, in the majority of the patients (ranging from 90% at the level of the MVA to 14% at the level of the distal CS). The minimal distance between the CS and MVA was 5.1±2.9 mm. In patients with severe mitral regurgitation, the minimal distance between the CS and the MVA was significantly greater as compared with patients without severe mitral regurgitation (mean 7.3±3.9 mm versus 4.8±2.5 mm, P<0.05). Conclusion— In the majority of the patients, the CS courses superiorly to the MVA. In 68% of the patients, the circumflex artery courses between the CS and the mitral annulus. Multislice computed tomography may provide useful information for the selection of potential candidates for percutaneous mitral annuloplasty.

Noninvasive Evaluation With Multislice Computed Tomography in Suspected Acute Coronary Syndrome: Plaque Morphology on Multislice Computed Tomography Versus Coronary Calcium Score

OBJECTIVES Our aim was to evaluate the atherosclerotic plaque burden and morphology as determined by 64-slice multislice computed tomography (MSCT) coronary angiography in relation to the calcium score in patients presenting with suspected acute coronary syndrome (ACS). BACKGROUND The absence of coronary calcium during coronary calcium scoring has been proposed to rule out significant coronary artery disease (CAD). However, data in patients presenting with suspected ACS are scarce. METHODS In 40 patients (age 57 +/- 11 years, 26 men) presenting with suspected ACS, MSCT coronary angiography in combination with coronary calcium scoring was performed before conventional coronary angiography. MSCT angiograms were evaluated for the presence or absence of coronary atherosclerotic plaque and the presence or absence of obstructive (> or =50% luminal narrowing) CAD. In addition, plaque type was determined, and findings were related to the calcium score. RESULTS Coronary artery disease was observed in 38 patients, of whom 10 patients had nonobstructive and 28 patients had obstructive CAD, confirmed by conventional coronary angiography in all patients. In patients with CAD, plaques were distributed as follows: 39% noncalcified plaques, 47% mixed plaques, and 14% calcified plaques. Coronary calcium was detected in 27 patients, of whom 10 had a score >400. In 13 (33%) patients, no coronary calcium was observed, but in 11 (85%), atherosclerotic plaques were detected on MSCT angiography. CONCLUSIONS In patients presenting with suspected ACS, noncalcified plaques are highly prevalent and the absence of coronary calcium does not reliably exclude the presence of (significant) atherosclerosis. This information may be of value to improve our understanding of the potential role of MSCT in this patient population.

Incremental prognostic value of multi-slice computed tomography coronary angiography over coronary artery calcium scoring in patients with suspected coronary artery disease

AIMS The purpose of this study was to assess the relationship between calcium scoring (CS) and multi-slice computed tomography coronary angiography (MSCTA) and to determine if MSCTA has an incremental prognostic value to CS. METHODS AND RESULTS In 432 patients (59% male, age 58 +/- 11 years) referred for cardiac evaluation owing to suspected coronary artery disease (CAD), CS and 64-slice MSCTA were performed. The following events were combined in a composite endpoint: all-cause mortality, non-fatal infarction, and unstable angina requiring revascularization. CS was 0 in 147 (34%) patients, CS 1-99 was present in 122 (28%), CS 100-399 in 75 (17%), CS 400-999 in 56 (13%), and CS > or = 1000 in 32 (7%). MSCTA was normal in 133 (31%) patients, MSCTA 30-50% stenosis was observed in 190 (44%), and MSCTA > or =50% stenosis in 109 (25%). During follow-up [median 670 days (25th-75th percentile: 418-895)], an event occurred in 21 patients (4.9%). After multivariate correction for CS, MSCTA > or = 50% stenosis, the number of diseased segments, obstructive segments, and non-calcified plaques were independent predictors with an incremental prognostic value to CS. CONCLUSION MSCTA provides additional information to CS regarding stenosis severity and plaque composition. This additional information was shown to translate into incremental prognostic value over CS.